The inventive concept generally relates to memory devices, and more particularly, to a memory device, a memory system, and a method of controlling a read voltage of the memory device.
The volatile memory devices are characterized by the loss of stored contents at a power-off condition. Examples of volatile memory devices include certain types of random access memory (RAM) such as a static RAM (SRAM), a dynamic RAM (DRAM), a synchronous DRAM (SDRAM), and the like. In contrast, nonvolatile memory devices are characterized by the retention of stored contents even during power-off condition. Examples of nonvolatile memory devices include a read only memory (ROM), a programmable ROM (PROM), an electrically programmable ROM (EPROM), an electrically erasable and programmable ROM (EEPROM), a flash memory device, a phase-change RAM (PRAM), a magnetic RAM (MRAM), a resistive RAM (RRAM), a ferroelectric RAM (FRAM), and the like.